Britney and Franco are taking turns riding a dirt bike. Britney goes first, covering 4.7 miles in 18 minutes. Next Franco, who likes to go fast, goes 5.4 miles in 12 minutes. What was the average speed for the two riders?

Question

Write your answer as a whole number or as a decimal rounded to the nearest tenth.
miles per h

Answer 1

To find the average speed of both riders, we need to calculate the total distance they covered and the total time they took, then use the formula:

\[ \text{Average Speed} = \frac{\text{Total Distance}}{\text{Total Time}} \]

Step 1: Calculate total distance.

Britney rode 4.7 miles and Franco rode 5.4 miles.

\[ \text{Total Distance} = 4.7 \text{ miles} + 5.4 \text{ miles} = 10.1 \text{ miles} \]

Step 2: Calculate total time.

Britney took 18 minutes and Franco took 12 minutes.

\[ \text{Total Time} = 18 \text{ minutes} + 12 \text{ minutes} = 30 \text{ minutes} \]

Step 3: Convert total time from minutes to hours.

Since there are 60 minutes in an hour, we convert 30 minutes to hours:

\[ \text{Total Time in Hours} = \frac{30 \text{ minutes}}{60} = 0.5 \text{ hours} \]

Step 4: Calculate average speed.

Now we substitute the total distance and total time into the average speed formula:

\[ \text{Average Speed} = \frac{10.1 \text{ miles}}{0.5 \text{ hours}} = 20.2 \text{ miles per hour} \]

Thus, the average speed for the two riders is:

\[ \boxed{20.2} \text{ miles per hour} \]